A LETTER in the "Christian Advocate" for March 22d denies the charges made in my article in the "Monthly" for March, as to the unhygienic condition of Ocean Grove during the crowded periods of past seasons. An editorial in the same number of the "Advocate" and another two weeks later call attention to this letter, and challenge "The Popular Science Monthly" "either to prove or retract" these charges. The editor, who says that he is "without personal knowledge" of the conditions of the place, assumes that Ocean Grove has been slandered from anti-religious motives, and avers "that the determining reason which animated the singling out of Ocean Grove for special mention as a sinner above all others in sanitary matters was, . . . because it was, as the writer phrases it, a religious resort."

Now, the writer indignantly disclaims the charge that the question of religion presented itself to her mind. It would, indeed, be a strange association of ideas that could make her attack on bad sewage an assault upon religion. Moreover, it is evident that this editor was not only "without personal knowledge" of the place he champions, but that he was also without personal knowledge of the article which he criticises. Otherwise he presumably would not apply the masculine gender to a writer giving a name purely feminine, nor complain of the "singling out of Ocean Grove," when it was one of six places mentioned, and only twelve lines were given to it. That I was not alone in my criticism is naively acknowledged by the editor in characterizing it as "one of various unwarranted attacks," and in his saying that "Ocean Grove has not been excepted from the unfavorable comments" that have been made on various sea-side resorts, and that "the intimations have continued and become rumors detrimental to the character of the place as a health resort."

The letter above referred to is from the Rev. E. H. Stokes, President of the Ocean Grove Camp-Meeting Association. Mr. Stokes says: "All our large hotels, and many of our larger cottages, eighty in number, have sewer connections . . . The sewer runs up into the camp-ground occupied by tents, and takes off all the deposits, both of privy and cesspool from there. The grounds on which the tents are located are thoroughly raked over every morning, and the air is pure." From the writer's personal observation extending over a period of three summers, she denies that the sanitation of Ocean Grove was then even tolerably good. Her account, written in August, 1882, on the spot, and sent to the "Monthly" in September, did not overestimate the crowding, nor the effects of the imperfect means which existed for removing fecal accumulations. This was matter of common repute; everybody could smell the vile odors, and many physicians denounced the unsanitary condition of the place. Both the State and the National Boards of Health took notice of these things in their reports for 1882. The former states that in Ocean Grove "the system of water-closet disposal is varied, and depends too much upon the will of each family. The town should ultimately adopt cither a public system of weekly dry removal, or connect all closets, both in-doors and out, with a sewer system." It is further advised because Ocean Grove is "so much of a camping-place for the summer, that to the parts thus occupied the strict rules of military sanitary police should be applied and executed by an inspector constantly on duty." "The Sanitarian" for April 5, 1883, published an abstract of a "Report on the Atlantic Coast Resorts," made by E. W. Bowditch, C. E., to the National Board of Health, in which is this statement: "The watering-places on the Atlantic coast of New Jersey are all more or less in a transition state; few have adequate water-supplies, and none are supplied with sewers." Dr. Bowditch thus practically ignored the attempts at sewerage made by the authorities of Atlantic City and Asbury Park, as well as of Ocean Grove.

These authorities, and the statement of the writer's own experience, will perhaps refute the "Advocate" editor's assertion that, "without knowledge of any facts, the reckless charges were penned," and the still more vigorous language of the Rev. Mr. Stokes, who arrogates a thorough know ledge of the five other places criticised, when he writes, "I pronounce the whole article false"! A virtual confession of the truth of the charges is made by the activity displayed during the winter in remedying the causes of complaint. Faults in construction of the Asbury Park sewers have been remedied, and some eighteen thousand feet of sewer-pipe have been laid in Ocean Grove. Fletcher Lake, which last summer was filled with muck, has been cleaned out and transformed into a respectable body of water. These and other hygienic improvements which have followed in the wake of the fault-finder will doubtless render Ocean Grove and its close neighbor, Asbury Park, satisfactory places for visitors during the season of 1883. That the past winter's work is likely to prove efficient may be gathered from Mr. Stokes's letter, in which he says, "The State Board of Health reports that the sanitary matters of the Grove progress satisfactorily."

It is hoped that the pleasure with which this account is given of a better sanitary prospect for the present summer over that of former years will prove previous charges of improper drainage to have been made only in that spirit which sounds an alarm to prevent danger.

Alice Hyneman Rhine.

COST OF LIFE.

Messrs. Editors:

In an article in the June number of your magazine, entitled "Cost of Life," there are some mathematical calculations, or rather blunders, that make one wonder how they could have been put forth in any journal, though making less claims to science than your valuable magazine. It is gravely stated that a man weighing 150 pounds upon the earth would, upon the planet Jupiter (having 300 times the earth's mass), weigh 45,000 pounds = 2241⁄2 tons. The relative mass of Mars is said to be 1⁄60 that of the earth, and, therefore, the man spoken of above would weigh only 21⁄2 pounds upon Mars. Now, if the law of attraction as first announced by Newton, and now taught to every schoolboy, is correct, the weight of the above man upon Jupiter would be 2∙55 (two and 55⁄100) times his weight upon the earth = 3821⁄2 pounds—enough to make him decidedly uncomfortable, but still not quite 221⁄2 tons. In regard to Mars there are two errors: first, his mass is 11⁄100 that of the earth, not 1⁄60 as stated; second, if it were 1⁄60 it would not be right to divide 150 by 60, for that would disregard a very essential part of the great law or laws of gravitation. If the radius of Mars is ∙52 that of the earth, would not the supposed man weigh, if placed upon his surface, 61 pounds?

There may be some errors in these corrections, but I think they are trifling compared with those in Mr. Pratt's article.

R. S. Bosworth.

Waterton, New York,May 21, 1883.

Messrs. Editors:

Allow me to call attention to certain assertions in the article headed "Cost of Life" in the June number of your journal. The points I speak of relate to gravity on the planets, and the statements made in regard thereto. It is declared that a man of 150 pounds weight would on Jupiter weigh about 45,000 pounds. It is an elementary truth in physics that gravity decreases as the square of the distance increases; wherefore, although Jupiter is more than 300 times as heavy as the earth, its diameter is more than eleven times that of the earth, and the relative weight must be divided by the square of the ratio. In this case the divisor is more than 121. The best determinations of the force of gravity on Jupiter give it at a little less than two and three fourths that on the earth. So the man of 150 pounds would, on Jupiter, weigh about 400 pounds, not that enormous figure quoted above.

So, gravity on Mars is more than half that on the earth, and our man would weigh 80 pounds, not 21⁄2 as given in the article. Every similar statement in the whole course of the discussion is as badly in error as these here noticed.

It is well known that the destructive effect of a bullet fired by an explosive depends not on the power of gravity, but on that of the powder; and the philosophers who, on Mars, should attempt to catch bullets in their hands, might rue their philosophy. As science, the article harmonizes well with the kind in which Jules Verne is accustomed to indulge.